1. Field of the Invention
This invention is related to the feed means for reactors used for chemical or catalytic conversion of hydrocarbons and to reactors used for metallurgical processes. Such reactors frequently use highly erosive materials such as particulate catalysts and particulate coke. High temperature levels are also characteristic of such reactors. The combination of characteristics creates the erosion and breakdown of reactor components, including feed means for said reactors.
When the feed means constitute nozzles having relatively small diameter orifices, but high feed material output, the potential for erosion of the nozzle becomes a significant factor in continuous reactor operation. Such erosion can effect the pattern of the discharge of said nozzle inside said reactor, as well as causing total shutdown of the effected nozzle when erosion causes reactants to backflow into said nozzle.
Repairs to feed nozzles and components create delays in reactor time of use, as well as the efficiency of such reactors during long periods of use between nozzle repairs.
2. Prior Art
The prior art has addressed the problem of feed nozzle erosion in reactors by constructing such nozzles of various materials of increased strength and non-reactivity, such as nickel-chrome steels and refractory packings. The specialty steels are hard to machine, and the costs for such materials are very high.
Other attempts at producing durability of reactor feed nozzles have included the reduction of the temperature conducive to reactivity and erosion by incorporating fluid coolant flow paths in said nozzles as well as providing interchangeability of nozzle components.
In U.S. Pat. No. 4,123,042 to Pearce et al, a tuyere for a metallurgical furnace is disclosed which has an inner and outer tuyere jacket. The jackets are sealed from each other by a fluid, high temperature grout pumped into the space between the jackets and solidified.
U.S. Pat. No. 3,236,281 to Bain et al provides a fuel burner nozzle for an open hearth furnace. The furnace nozzle has a coaxial arrangement of several tubular pipe conduits for supplying diverse materials to the furnace, such as fuel, gas and steam.
In U.S. Pat. No. 299,536 to Hartman, a removable tuyere is disclosed. The tuyere is tapered and fits directly into and against a similarly tapered collar which is permanently affixed within the furnace side wall. This structure provides replaceability of the tuyere but fails to provide longevity of the tuyere because of the absence of any insulative structure for the tuyere from furnace temperature. In addition, the tapered fit of the tuyere and its cover are expensive to manufacture.